Narrative:

I needed to fly my plane to ash. I regularly fly to both ash and psm. Another pilot was flying his bonanza behind me, to fly me home after dropping off my plane. I mistakenly entered psm in the GPS. About 1/2 way into the flight, the other pilot called from his airplane, wondering why we were headed in slightly different directions. It is then that I changed the destination to ash from psm. However, before takeoff, I had used the GPS to retrieve the ATIS and tower frequency for my destination, as I usually do. When in mid flight, I changed the destination, I did not update the ATIS and tower frequency on the GPS. When I called in to the tower, I was actually talking to psm, but flying to ash. It was not until I was on short final at ash that I realized my error, quickly changed to ash tower, and landed uneventfully, with no apparent traffic conflicts. The tower controller told me to call him. I did. He said he was going to report the incident, as he was having a very bad day, with other problems with other aircraft all morning long. The tower controller would not let me explain why I was on the wrong frequency.

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Original NASA ASRS Text

Title: UNAUTH UNCOORD CLASS D AIRSPACE ENTRY WHEN THE PLT OF A BE35 ENTERS THE WRONG DEST IN HIS GPS, LATER NOT CHANGING THE PRESELECTED TWR FREQ TO ASH, NH.

Narrative: I NEEDED TO FLY MY PLANE TO ASH. I REGULARLY FLY TO BOTH ASH AND PSM. ANOTHER PLT WAS FLYING HIS BONANZA BEHIND ME, TO FLY ME HOME AFTER DROPPING OFF MY PLANE. I MISTAKENLY ENTERED PSM IN THE GPS. ABOUT 1/2 WAY INTO THE FLT, THE OTHER PLT CALLED FROM HIS AIRPLANE, WONDERING WHY WE WERE HEADED IN SLIGHTLY DIFFERENT DIRECTIONS. IT IS THEN THAT I CHANGED THE DEST TO ASH FROM PSM. HOWEVER, BEFORE TKOF, I HAD USED THE GPS TO RETRIEVE THE ATIS AND TWR FREQ FOR MY DEST, AS I USUALLY DO. WHEN IN MID FLT, I CHANGED THE DEST, I DID NOT UPDATE THE ATIS AND TWR FREQ ON THE GPS. WHEN I CALLED IN TO THE TWR, I WAS ACTUALLY TALKING TO PSM, BUT FLYING TO ASH. IT WAS NOT UNTIL I WAS ON SHORT FINAL AT ASH THAT I REALIZED MY ERROR, QUICKLY CHANGED TO ASH TWR, AND LANDED UNEVENTFULLY, WITH NO APPARENT TFC CONFLICTS. THE TWR CTLR TOLD ME TO CALL HIM. I DID. HE SAID HE WAS GOING TO RPT THE INCIDENT, AS HE WAS HAVING A VERY BAD DAY, WITH OTHER PROBS WITH OTHER ACFT ALL MORNING LONG. THE TWR CTLR WOULD NOT LET ME EXPLAIN WHY I WAS ON THE WRONG FREQ.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.